High power OPCPAs above 10 W at short-wave IR wavelengths (SWIR: 1.4 - 3 μm) may be limited because of thermal heat dissipation in the nonlinear crystals. In this work we provide up-to-date measurements of the absorption coefficients of the nonlinear crystals used at these wavelengths and simulations of the thermal effects on critical parameters. In particular, power scaling limits will be discussed.
Quasi-phase matching (QPM) can be used to increase the conversion efficiency of the high harmonic generation
(HHG) process. We observed QPM with an improved dual-gas foil target with a 1 kHz, 10 mJ, 30 fs laser
system. Phase tuning and enhancement were possible within a spectral range from 17 nm to 30 nm. Furthermore
analytical calculations and numerical simulations were carried out to distinguish QPM from other effects, such
as the influence of adjacent jets on each other or the laser gas interaction. The simulations were performed with
a 3 dimensional code to investigate the phase matching of the short and long trajectories individually over a
large spectral range.
Optical parametric chirped-pulse ampliﬁcation (OPCPA) is the most promising method for providing compact, wavelength tunable, high power, femtosecond lasers. We have recently achieved a 112 W OPCPA with wavelength tunability around 800 nm and 30 fs pulse duration in burst mode (100 kHz in a 800 µs burst at 10 Hz). In this work, we discuss the various laser architectures and the critical parameters in achieving similar laser parameters but in continuous operation.